Triangle Enlargement Find Coordinates Of Vertices A' And B'

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In the realm of geometric transformations, enlargement stands as a fundamental concept, playing a crucial role in scaling shapes and figures while maintaining their overall form. When an object undergoes enlargement, its dimensions expand or contract proportionally, governed by a scale factor centered around a specific point. In this comprehensive exploration, we will delve into a specific scenario involving triangle ABC undergoing enlargement with a center at (-2, 3) and a scale factor of -1/2, resulting in triangle A'B'C'. Our primary focus will be on determining the precise coordinates of vertex A' and vertex B' after this transformation. The intricacies of geometric transformations often present a challenge to students and enthusiasts alike, and this detailed explanation aims to demystify the process. By carefully dissecting each step, we will provide a clear and concise methodology for solving similar problems, fostering a deeper understanding of enlargement and its practical applications in geometry. We will first revisit the underlying principles of enlargement, emphasizing the significance of the center of enlargement and the scale factor. Then, we will meticulously apply these principles to calculate the coordinates of the transformed vertices. This approach not only answers the immediate question but also equips readers with a robust framework for tackling a wide range of geometric transformation problems.

Before we embark on the calculation of vertex coordinates, it is essential to firmly grasp the core concepts underpinning enlargement. Enlargement, in essence, is a geometric transformation that alters the size of a figure while preserving its shape. Two key elements govern this transformation: the center of enlargement and the scale factor. The center of enlargement acts as the fixed point around which the figure expands or contracts. Imagine it as the anchor point for the transformation. All points on the original figure will move radially away from or towards this center during enlargement. The scale factor, on the other hand, dictates the magnitude of the enlargement. A scale factor greater than 1 indicates an expansion, meaning the figure will become larger. Conversely, a scale factor between 0 and 1 implies a reduction, shrinking the figure. A negative scale factor introduces an additional element: a reflection through the center of enlargement. In our specific scenario, the center of enlargement is given as (-2, 3), and the scale factor is -1/2. This means that the triangle will not only be reduced in size by half but also reflected through the point (-2, 3). To effectively determine the coordinates of the transformed vertices, we must understand how these two parameters interact. The distance between a point on the original figure and the center of enlargement will be multiplied by the scale factor to determine the corresponding distance on the enlarged figure. Furthermore, the direction of this displacement will be reversed due to the negative scale factor. The process involves a careful application of vector arithmetic and coordinate geometry, which we will explore in detail in the subsequent sections.

To calculate the coordinates of vertex A' after the enlargement, we need to know the initial coordinates of vertex A. Let's assume the coordinates of vertex A are (x, y). The process involves a few key steps that leverage vector operations and the properties of enlargement. The first step is to determine the vector pointing from the center of enlargement to vertex A. This vector, which we'll call vector CA, can be calculated by subtracting the coordinates of the center of enlargement (-2, 3) from the coordinates of vertex A (x, y). Thus, vector CA = (x - (-2), y - 3) = (x + 2, y - 3). Next, we multiply this vector CA by the scale factor, which is -1/2 in our case. This multiplication scales the vector, reflecting the change in distance due to the enlargement. The scaled vector is given by (-1/2)(x + 2, y - 3) = (-1/2(x + 2), -1/2(y - 3)). This scaled vector represents the displacement from the center of enlargement to vertex A'. To find the actual coordinates of A', we add this scaled vector to the coordinates of the center of enlargement (-2, 3). The coordinates of A' are therefore (-2 + (-1/2(x + 2)), 3 + (-1/2(y - 3))). Simplifying this expression, we get the coordinates of A' as (-2 - 1/2x - 1, 3 - 1/2y + 3/2) = (-3 - 1/2x, 9/2 - 1/2y). Therefore, the coordinates of vertex A' depend on the initial coordinates of vertex A. Without knowing the initial coordinates of A, we cannot provide a numerical answer. However, this formula allows us to calculate the coordinates of A' for any given coordinates of A. Understanding this process is crucial for solving similar enlargement problems in geometry.

The process of determining the coordinates of vertex B' mirrors the methodology we employed for vertex A'. To initiate the calculation, we must first establish the initial coordinates of vertex B. Let us denote these coordinates as (p, q). Following the same principle as before, the initial step involves calculating the vector extending from the center of enlargement (-2, 3) to vertex B (p, q). We'll denote this vector as vector CB. To find vector CB, we subtract the coordinates of the center of enlargement from the coordinates of vertex B, yielding vector CB = (p - (-2), q - 3) = (p + 2, q - 3). The next crucial step is to scale this vector by the enlargement's scale factor, which, in our case, is -1/2. Multiplying vector CB by -1/2 effectively adjusts the length of the vector according to the scale factor and incorporates the reflection due to the negative sign. The scaled vector is calculated as (-1/2)(p + 2, q - 3) = (-1/2(p + 2), -1/2(q - 3)). This scaled vector represents the displacement from the center of enlargement to the transformed vertex B'. To pinpoint the precise coordinates of B', we add this scaled vector to the coordinates of the center of enlargement (-2, 3). The coordinates of B' are thus given by (-2 + (-1/2(p + 2)), 3 + (-1/2(q - 3))). Simplifying this expression allows us to express the coordinates of B' in terms of p and q: (-2 - 1/2p - 1, 3 - 1/2q + 3/2) = (-3 - 1/2p, 9/2 - 1/2q). Consequently, the coordinates of vertex B' are intrinsically linked to the initial coordinates of vertex B. Without specific numerical values for p and q, we cannot provide a definitive numerical answer for the coordinates of B'. However, this derived formula provides a direct means to calculate the coordinates of B' for any given coordinates of B. Mastering this calculation process is paramount for proficiently addressing similar enlargement problems in the field of geometry.

In conclusion, we have explored the process of enlarging triangle ABC with a center at (-2, 3) and a scale factor of -1/2 to obtain triangle A'B'C'. Our primary focus was on determining the coordinates of the transformed vertices A' and B'. We established that the coordinates of A' and B' are dependent on the initial coordinates of vertices A and B, respectively. Specifically, if the initial coordinates of A are (x, y), then the coordinates of A' are (-3 - 1/2x, 9/2 - 1/2y). Similarly, if the initial coordinates of B are (p, q), then the coordinates of B' are (-3 - 1/2p, 9/2 - 1/2q). These formulas provide a direct method for calculating the transformed coordinates once the original coordinates are known. The negative scale factor plays a crucial role in this transformation, not only scaling down the triangle but also reflecting it through the center of enlargement. This understanding is fundamental in grasping the nature of geometric transformations. By applying the principles of vector arithmetic and coordinate geometry, we have successfully navigated the complexities of enlargement. This approach not only answers the immediate questions regarding the coordinates of A' and B' but also equips readers with a robust framework for tackling a wide range of geometric transformation problems. The key takeaways from this exploration include the importance of the center of enlargement, the role of the scale factor, and the application of vector operations in determining the transformed coordinates. With a firm grasp of these concepts, students and enthusiasts can confidently approach and solve similar geometric challenges.